Researchers from MIT discovered that under a powerful magnetic field and at very low temperatures, graphene can filter electrons according to the direction of their spin. This is something that cannot be done by any conventional electronic system - and may make graphene very useful for quantum computing.
it is known that when a magnetic field is turned on perpendicular to a graphene flake, current flows only along the edge, and in one direction (clockwise or counterclockwise, depending on the magnetic field orientation), while the bulk graphene sheet remains insulating. This is called the Quantum Hall effect.